1. Field of the Invention
The present invention relates to a method and a device for energy recovery having a hydrostatic engine, at least one hydraulic store, which is connected to the hydrostatic engine via an operating line, and having a valve device which influences a volume flow rate in the operating line between the hydraulic store and the hydrostatic engine.
2. Description of the Background Art
DE 10 2004 043 897 A1, which corresponds to U.S. Pat. No. 7,526,919, discloses a device for recovering kinetic energy which is released during a braking operation. The device has a hydrostatic engine which is connected to a storage element by means of an operating line. A valve device is arranged in this operating line. This valve device is constructed as a switching valve and can be switched between a connecting and a separating switching position. Consequently, it is possible to uncouple the hydraulic store from the hydrostatic engine and consequently to prevent unintentional discharging and consequently a loss of the recoverable energy. The hydrostatic engine can be connected by means of a coupling device to a drive chain, for example, of a vehicle.
In the prior art system, it is disadvantageous for only complete decoupling or an unthrottled connection to be possible between the hydrostatic engine and the hydraulic store. Therefore, it is only possible to influence the hydrostatic braking by the hydrostatic engine by adjusting the hydrostatic engine itself. The possibilities for application and expansion of a hydrostatic travel drive are consequently limited owing to a lack of flexibility.